The physicist studies the behavior of nature through experiments and translates his observations into mathematical models. It studies the structure of the material world, from the infinitely small (atom) to the infinitely large (cosmos). Basic research in physics helps to develop a deep understanding of nature by bringing to light the fundamental laws (theory) that govern natural phenomena, while experimental physics is concerned with the observation, measurement, extrapolation, design and performance of experiments. It leads to practical and innovative applications in various fields: optics, electronics, thermics, mechanics, materials, fluids… Depending on the orientation of the physicist (fundamental research or experimental physics), the profession can be carried out in a research laboratory public, within a university research unit as a teacher-researcher or in an industrial company as a research or process engineer Project manager in computer science or telecommunications, radiophysicist at the hospital and energy specialist industrial are examples of positions open to physicists. Abstraction ability, aptitude for calculation, curiosity, perseverance and rigor are qualities and skills essential to exercise this profession.